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Hi there experts. Happy holidays. I'm having trouble with my wagon and I hear this is a great place to turn for help. There are a lot of moving parts here, and I apologize for the length, but I want to be thorough.
I'm trying to diagnose white exhaust smoke that appears only when the car is standing still and a fast idle that occurs in P and N only. Sounds like a head gasket and/or vacuum leak, right? Well, maybe. I have no milkshake in the oil, no coolant loss, no bubbles in coolant. The cylinders all show relatively fast compression to 190-200 PSI. Each cylinder tests within that range from test to test. I have a cheapo Harbor Freight compression tester and can't get any of the adaptors to screw in so I was using the handheld rubber fitting.
My background: I had a '75 wagon in the 90s, carrot color, and loved it until it died. I needed a wagon for my mastiff and hauling music gear so I picked up a neglected '87 240 DL wagon about 3 months ago. I specifically picked a 240-series Volvo both because I missed my old one and because I'd read you can learn to work on them yourself, and I picked up a decrepit one because I prefer to get old things and fix them than get new things. Also because the car and everything I've put into so far cost less than the dealer estimate to replace the mirror some jerk just knocked off my parked Audi without leaving a note. I never changed my own oil until this week. I'm reasonably handy though and willing to research and work patiently. Since then I've probably spent 40-hours working on it, figuring it out, and a whole bunch more reading and researching. I got a Haynes, then a Chilton (yeah, I know), then a Bentley. I lucked out and discovered there's a great Volvo mechanic down the road a couple of miles. That said, I want to do as much myself as I can. I've become familiar with my area junk yards and auto parts stores.
Initial symptoms on purchase: fast, unstable idle, nasty exhaust smell (mechanic describes as over-rich fuel mixture), low power, yadda yadda. Temp sensor seemed to move only a little and never got above about 1/6 from C to H. Mechanic pointed out that the front seals have leaked a lot of oil, and they are on the to-do list along with the timing belt and V-belts.
Work done (that I remember):
1. New air intake hose to throttle body and replacement of janky or disconnected vacuum hoses calmed idle but didn't get rid of smell.
2. plugs, wires, distributor cap, rotor brought engine to life. The old plugs were worn and had massive gaps, but were relatively consistent in appearance and didn't show any special symptoms (based on photos in the back of the Haynes).
2a (because I just remembered and don't want to renumber). Seafoam in gas, oil, and vacuum inlet (using the FPR hose), followed by Italian tuneup.
3. Cleaned MAF sensor with MAF sensor spray cleaner.
4. (unrelated: front and rear ipd sway bars, cheap blue tooth stereo and a couple of rear speakers to replace blown factory speakers, rear shocks, replaced large clock with tach and small clock, still locked in a losing battle with speedo/odo)
5. Pulled intake manifold. I discovered the wiring harness was threaded through it and I ended up removing both harnesses (LH2.2, Chrysler ignition) entirely. Then I discovered I could have just pulled the LH2.2 ECU end through the firewall, which I had to do anyway to get it through the manifold. Removed all the cracked, oil-soaked, filthy sheathing. Cleaned, retaped, and tested every single conductor. I DO NOT have crumbling wires. I did have some breaks, which I alternately soldered and shrink-wrapped and crimped using a ratcheting crimping tool. One was the negative wire to a fuel injector. And then tested. Rerouted oil pressure sender, alternator connection, and Chrysler vacuum hose around the firewall and passenger fender using conduit for the wires and keeping away from the exhaust manifold. I replaced the original stiff plastic vacuum tube with new vacuum line to the intake manifold. Reconnected harnesses. Ran conduit around alternator wire and ignition harness under crank shaft
6. Pulled flame trap and oil separator. The flame trap was original style and fully clogged. I could blow through the oil separator easily so I shook some brake cleaner up in it to get out the gunk that was there, let it air out for a few days and put it back in). Installed ipd flame trap relocation kit and flame trap. Installed IPD rear camshaft seal retainer.
7. Obtained junkyard intake manifold, fuel rail, and injectors FROM AN LH 2.4 ENGINE. Thoroughly cleaned out the new manifold and the TB with TB and / or carb cleaner. Installed manifold with a fresh gasket. There's no wire in an LH2.2 to connect to the cold start injector so I connected its fuel line but the electric socket is empty. Transferred the vacuum inlet from the LH2.2 manifold for the vacuum line to the Chrysler computer. Torqued bolts I could reach with my torque wrench to spec. Hand tightened the remainder as close as I could estimate with a closed end wrench.
8. Reinstalled original throttle body (with fresh gasket) because the 2.4 TB didn't have the idle air control module. Adjusted and tested throttle line and position sensor ("click"). Torqued the single bolt I could reach with torque wrench to spec and hand-tightened the other two as close as I could guess.
9. Removed all fuses, hosed down the fuse holders with contact cleaner and wire brushed to remove corrosion, and replaced with new fuses.
10. Changed the oil. It's still dirty. I need to do it again. This is the third oil change since I bought the car, but the first oil change I've ever done myself. Fortunately not rocket science. Valvoline maxlife 10W30. New Bosch filter hand tight, old gasket fully removed, drain plug hand threaded and retightened to torque spec.
11. Changed transmission fluid via pan drop and replaced filter. That pan was a b*tch to get back on because the dipstick tube and the transmission have slightly different ideas about where the pan should be located (by about 1/2"). Finally did it by starting the tube threads and then pushing it to where I could get a bolt screwed in to position the pan. Drove on it for a while. Then flushed the transmission using the radiator method until fluid came out like new.
12. Drained coolant from radiator bottom hose and engine block to make sure water was moving through the engine and radiator. It was, and my hoses are good. Refilled with about two gallons. Installed new thermostat and housing. I replaced the green stuff that was in there (and caked on) with the O'reilly gold jug (universal, clear with an amber-ish tint) because it was on sale and I figured I would step up to something better when I ensure the car is running well. The temperature gauge reports engine temperature now. Stationary, at warm idle, the gauge sits dead center. I have noticed it vary between one-quarter and three quarters while test driving, but it has not overheated. I took it up some good hills too. The coolant expansion tank never gets hot enough I can't stick my finger in it.
13. Replaced oxygen sensor with new Bosch unit.
14. When I reassembled the harness, intake manifold, TB, and fired it up, I discovered a very high idle (~2000 rpm) in P/N, and the white exhaust smoke when stationary problem persisted. This is the computer doing this: it starts lower, then thinks for a minute and revs it up. When stopped with the brake in D/R/1/2, it idles at about 1000 rpm. Disconnecting the idle air controller prevents the idle from rising, so the IAC is doing something. Maybe even what it's supposed to. Spraying carb cleaner revealed no leaks. I grounded the idle test connector and closed the idle adjustment screw on throttle body all the way. This got it down to about 1000 rpm. Sounds like a leak somewhere, right? I can't figure out where. I've checked all the vacuum hoses and they seem fine. The manifold and throttle body have new gaskets. The only thing missing a gasket now is the idle air control attached to the throttle body, and it didn't have one before either.
15. MAF sensor passed hot-wire and pot-adjustment tests per Haynes/Bentley. Nonetheless, I replaced it with a rebuilt MAF sensor I pulled from a junkyard '87, same part number, and also testing well, to see if it made a difference. This brought the high idle down to about 1500. I set the mixture screw to the same resistance as the original (about 450), but no adjustments to the screw produce a discernable difference in operation. Disconnecting the MAF sensor from the harness brings the tachometer down to maybe 700-1000 with a loping dip on about a one-second rhythm.
Current state: The car drives smoothly and feels like it's about as powerful as it should be, but I still have the white exhaust smoke when the car is stationary and fast idle issues in P and N. The white exhaust smoke when stationary problem has seemed to increase somewhat, but it's also much colder here now (30s-40s) so perhaps more visible as well. When I asked the mechanic about it a few weeks ago, he suggested that if it doesn't happen until the exhaust system heats up it might be condensation burning out of the muffler. At this point it starts within 30 seconds of starting the car and continues at red lights and when stopped for more than a few seconds, long after I'd think any exhaust condensation would have burned off. It does drip water form the tailpipe. The smoke is more pronounced in P and N (perhaps because of the fast idle) but still present in D. It appears to go away while driving the car.
Known issue: The plastic electrical clip that on my distributor is no longer attached to the distributor and has a weak connection so wiggling it kills the engine. It seems just fine when left dangling in its preferred position, but that's obviously not sustainable. This left me in a very uncomfortable no-start situation until I figured it out. I picked up a junkyard distributor and I have a replacement plastic piece on order.
Here are my current theories and prescriptions:
A. I have a small head gasket leak that was aggravated by 1) the Seafoam cleaning out debris, 2) new plugs putting more pressure on the engine, and 3) lots of Italian tune-up. It's not enough or positioned in such a way as to create a discernable loss of coolant, bubbles in coolant expansion tank, or milky oil. Over time it will get worse and I will begin to see it while the car is moving. I should test the gasses from the coolant expansion tank. I probably need to remove the cylinder head, look closely at the gasket and engine for evidence of issues, and do the usual head gasket things.
B. I have an as-yet undiagnosed vacuum leak. I should go over the manifold and TB area with a stethescope and a rubber hose until I find it. Also go back and re-check bolts on intake manifold and TB. Get a gasket for the idle control unit.
C. The claim that you can't disconnect and reconnect the Chrysler ignition computer because the connector is one-shot only (which I discovered only after removing the harness) is in fact true and somehow bad connections at the computer are causing the fast idle or in some way the white exhaust. I need to find a new ignition wiring harness.
D. I don't know what I'm doing and should leave this to a pro. No way, dude. As I pulled the thread on the sweater I realized I might have to get it towed to the shop, but instead it's running. I'm going to work this as far as I can before throwing up my hands.
If you've read this far, thank you. I'd be grateful for any advice you can offer. Photos on demand. Please don't be shy about telling me what I've screwed up - I want to learn.
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Hi,
The engine is getting way too much air!
Double check the throttle plate for it to be completely closed in the bore.
All the air coming into the engine must go through the AMM.
From there the IAC must have total control of the air flow for idling only.
The TPS has to tell the computer to use the idle program so, it has to be clicked closed to do this.
If you follow the procedures in the Bentley, it will tell you to turn the throttle stop screw 3/4(?) after you have it completely closed. This amount of partial turn past its contact point, with the shafts lever, is bogus. It doesn’t work well with the K Jet either but they used the black knob.
You want to give it about 1/8 turn “up” or about One to One Thirty on a clocks face going clockwise.
This screw is to used to hold the plate from jamming in the bore because of a springs return pressure.
After you achieve this, you adjust the TPS to click again only after you see the throttle plate barely wiggle open.
This triggers the computer to switch over to a run up program. The TPS causes a take over, of which, is a transitional shift of air flow.
Another program is initiated that changes the mixture and timing in relation to the AMM output signal changing. All this while, its reading the O2 sensor and RPM’s to move the IAC, if needed.
The IAC needs to be in good working order. This you listen for!
To be Cleaned out enough to race over the idle speed every time the engine is started and bring it back down.
This is the ends doing anything more mechanically as the IAC works with this setup to allow air around the throttle. The black knob cannot affect anything unless you are grounding out the IAC to prove you have no other air in.
This is a backward step and is a leftover from the K Jet days!
The IAC should only respond to a misfire, the alternator loading or A/C loading with a blip up of idle speed. The computer is always watching for the 750 rpm of the distributors hall sensor and acts fast to hold that.
If it goes any higher, the program in the ECU is written to do it, let’s say for the A/C on some cars.
That could be as high as 1000 rpm on the big bore, two piston, reciprocal compressors of the early eighties. Back on those years a controlled vacuum leak was introduced electrically to raise the idle.
As far as the white smoke, most of the time it is excess condensation. It comes from the process of fuel combustion and/or the humidity in the air that got sucked into the engine.
This moisture can condense anywhere south of the engine as the exhaust gases cool.
It can be a sign of that the thermostat is to cool or broken in the open position.
I think you cured that if the gauge needle is now going horizontal. I like 92C Wahler thermostats.
A lot of this moisture always stays right inside most mufflers.
Cars that run short distances keep enough of it around. Sometimes, you will see it pour out the exhaust pipes upon the accelerations from stop lights or up a grade.
The full size cars, of the Ford’s Crown Victoria’s vintage, are really bad.
The very rear muffler on our Volvo’s are a huge too. Acting like heat sinking moisture tanks, with a regular rust out issue. IMHO.
You need to smell the vapors for a Coolant fragrance or unburned Gasoline or drive it faster and more in cold weather.
You made a nice post and a good read!
A great substitution for old Christmas tales!
Happy holidays to all!
Phil
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Dear Phil,
You are a Christmas miracle, like Clarence in It's a Wonderful Life. Thank you for your detailed help. This was exactly it. What a difference a little bitty screw makes! It's not solved all the way. I need to drive it some more to see if it settles down, but opening up the set screw and lengthening the connecting arm has helped tremendously, with a corresponding massive decrease in tailpipe steam. Now I'm somewhere around 750 stopped in gear and maybe 1250 idling in P and N. If it doesn't finish fixing itself I will keep hunting for unmeasured air intake, i.e. leaks. But this was at least half the battle. It doesn't help that it's hovering just above freezing here and it's so humid that water is condensing on everything.
Now that I know what I was looking for I see where you had offered this advice before on this board. I recalled that when the manifold and throttle body were apart the throttle flap didn't seem to sit exactly the same as it was when connected to the old manifold. I looked for some way to adjust the limits of the throttle opening but found only the adjustable-length arm, missed that screw entirely, and didn't get that it was what the manuals were talking about. Now I basically understand how it works and things are on their way to just right.
Again, thank you very much for your help. Happy holidays!
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Hi,
I thank you for the Christmas salutations but I don’t feel that I helped you all that much. I’m sure that since you have the throttle plate shutting off the air, it helps.
The engine still should not idle above 750 rpm in any gear or out of gear. The engine may only temporarily rise in speed under the initial release of a load.
I’m concerned in hearing that you adjusted the connecting rod between the throttle spool and throttle plate shaft. You might be fighting yourself with that tease.
This will cause another problem if it is too short.
You don’t have to worry so much if it’s made longer. Making a too short of an adjustment, screws everything up on top!
You want the throttle plate shaft to be stopped only by the stop screw below.
The linkage rod adjustments are there for several variables between the right angle axial movements. These involve distances and the fit up of parts.
If you adjusted the rod too short the CABLE SPOOL has a built in tab along its circumference. It is possible, that now, it is catching on a fixed tab, that sticks out from a bracket, near the top of the spool.
These two tabs must barely touch or not touch. It’s best to have a tiny space or gap of say .005 of an inch when the throttle is completely closed in the bore.
The stop lever screw still has to be the only thing holding it there but not opened all!
This brings me too tell you about what else is needed when the throttle is all closed down.
You want to have a wee bit of slack in the throttle cable. The throttle cable is going around in a groove on the drum spool.
You do not want the cable tight as to hold the throttle open at all. You should be able to pinch the cable up with your fingers or put a pencil under it to a height of about 2 or 3 mm or not higher than the height of the sides of the grooves depth.
The slack is needed to allow for engine movements, since the engine and transmission are rubber mounted.
Both or one of these, can cause a higher idle beyond the control of the computer.
Keep us entertained with this project.
It could be a long winter for all!
Phil
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The connecting rod was set too short and I made it longer. Even when I retreated the screw the connecting rod was keeping the plate from closing all the way. So I popped it off the ball on the throttle body end and unscrewed first one turn, then another, so the set screw could come back farther as well and still connect with the plate on the axle that hits it. So just adjusting the screw made some difference, but didn't go far enough.
Interestingly enough, I also loosened the throttle cable in another effort to be sure that the set screw was the first limiting factor in the throttle plate's rotational limit. I think that's what you're saying, right? I probably loosened this a little more than was necessary, though the gas pedal is still reasonably reactive. I may need to reset the TPS as well. It had a hair trigger before but is probably requiring a wee bit of travel on the gas pedal before it takes the car out of idle. I'm not noticing that as a problem. Most of this was very rough adjustment under the cool lights of the Arco station. I have a busy week at work, but this weekend I'm going to take a longer, patient look at the whole assembly and dial it in closer to spec.
I drove the car to work today, an hour each way mostly at freeway speeds. The idle and steam are continuing to calm down. The idle seems right, or close too it, with the brake on in P and N. The P/N idle is still varying, from 1000 to 1500 on the dash panel tach, but I'm increasingly seeing it on the lower end of that. At one point it was in the 700-750 range.
And that time it burped. A little rough idle and some dark smoke from the exhaust. That happened only once, so I'm optimistic that it's a anomaly. Perhaps the engine burned off some old deposits and had to sneeze. Or maybe I'm going to need a fuel pressure regulator. Or maybe it's the faulty electrical connection to the distributor messing up the timing. I don't know.
Unfortunately I did start hearing some strange noises today from the front of the passenger side interior. Half whistle and half whirr. It started above 45 or 50 mph and increased in pitch and intensity with speed, not throttle. I'm hoping it's a quirky air leak perhaps because I replaced the passenger side mirror and haven't taken the time to put the interior piece back on without breaking it. But then I started noticing some other noise from that area I want to spend some time with.
Speaking of weird interior noises, is there something in the dashal region that should be spinning when the blower fan isn't running? I know my blower motor is shot and I will at some point need to dig in there to make a permanent stop to the fan rattle. Fortunately it still blows pretty well so it can wait til summer. But even all the way off it sounds like there's a similar smaller fan or something else rotating, also with some issues.
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Hi handy,
As to the fan noise, check that your air conditioning knob is fully off. I think if it's on any amount it causes the fan to operate on the lowest speed.
Peter
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The IDLE is adjusted on the 87 by grounding the idle air control motor and then adjusting the black knob on the throttle body. There is an empty 2 wired female connector hanging out by the coil or the 25 amp fuse, hook the striped wire to ground and this will disable the idle motor. Adjust accordingly.
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Hi there,
Boy, the setup was really off course adjustment wise. Guess that happens when swapping parts.
Yes, you have it correct! You want that little screw holding all the movement of the plates shaft down against it. Only adjust it up or back open about that 1/8 turn and lock it. Without a light in the bore behind the plate you will not see that it’s open any but it doesn’t take much for a lot of air to go by it.
If you want you can disconnect the linkage rod altogether but it removes the return spring pressure.
No big deal, as You will know the stop screw will hold up against the spring later. It’s just another way to do the same job.
As far as putting the rod back on right, you look at the top for those two tangs or tabs. Adjust the rod linkage system as I wrote in the other post with regards about gap and cable slack.
If you have noise in the cabin you can isolate all the vacuum going there by pinching off the vacuum line under the hood. A Quick isolation method.
This being bad or a leak inside under the dash somewhere will cause a high idle.
There is a one way check valve on top of the engines intake manifold.
I would say turn it around backwards to test the check valve but the hose sizes may not allow that.
It should only pass air in one direction. I suck on the valve for a test.
It should allow air to go towards the engine but not towards the cabin. There are two colors but I don’t remember which goes to the cabin.
Same for the brake booster line coming off the manifold. It has a check valve too! They do go bad as well.
One other place to check hoses is the one coming off the IAC. One side from it connects directly to the intake. For some reason it does not get a clamp as it fits tight from the factory.
Well that does not always stay that way! Give it some thought.
Father Time works on it when we are not out there in the cold of night at the local Arco station!
I feel for you man!
The whistling sound could be from the rubber plug in the firewall that you used to change out the harness. Maybe it is puckered! Not so much fr wind but noise could emanate in.
I just had a thought about you checking to see if two connectors on your harness are connected correctly. They probably are!
Both of thes look the same on the outside. One is for the throttle TPS and one for the Coolant Temperature Sensor, that the Computer uses. Under the third intake runner.
Not for the instrument cluster. It’s Sensor is more forward on the head.
I have read that sometimes people can get them switched, on some cars. I don’t know what the years are. Just give it a look.
You are having idle and possible mixture issues as these do talk to the computer. Just information!
Noises?
A hole open behind the air flow of the windshield can do a lot of noise at those speeds!
A fan noise? I don’t remember if it runs on it’s lowest speed all the time. The later year cars do as a requirement for ventilation and the defrost mode. The 240’s may have missed it! Climate controls and their headaches came much later.
I have not noticed it if they are so equipped.
Your stories on this car is like one Christmas gift that keeps on giving!
Looking forward to hearing about this weekends tales!
Good luck,
Phil
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Hi,
Looks like you're making some progress.
The temp gauge on my 240 will rise to 9'oclock after start up and stay there regardless of the ambient temp or my driving speed, within limits.
If you're seeing a fluctuation between 1/4 and 3/4 of the gauge length while you're driving, I think you may have a missing or inop thermostat.
If that is the case, it might explain why you're seeing condensation at the tailpipe for a longer than normal time.
Good luck,
Peter
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Thanks, Peter. I just swapped out the thermostat this weekend with the aftermarket 87 degree model from IPD and a new housing when I changed the coolant. I did put it handle side out, spring side in, with the air hole on top. With all the changes to the car I think it's taking some time to settle. Today it was much better. In initial idle it locks at nine o'clock. Occasionally it would get to about 9:15, 9:20, but never higher. After a while it seems to settle between 8:00 and 8:30 at freeway speed. I'm thinking next time I change the coolant I will put in the Wahler 92 model Phil prefers.
Even with that variation it's way better than before I replaced the thermostat, when it would barely ever rise above the cold line. I wonder if the old one had forgotten how to shut.
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posted by
someone claiming to be CB
on
Sun Dec 24 19:18 CST 2017 [ RELATED]
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so my first wagon was also a 75---B20 Engine.
My second wagon is also a, 87, but with an M47 5speed.
As for your list at the end:
A: head gasket is the last thing to consider
C: I've unplugged the harness from the VolvoChrylser Unit and have had no problems.
Idle:
Have you tried to adjust the CO on the AMM.
Cud be Your AMM is on the outs...cleaning a bad AMM will have no effect.
As to this- Is the AIRBOX thermostat working (does the car still have the heater Stove on the exhaust manifold and the Alum tube that brings that hot air into the AirBox(where the air filter is). That thermostat shud Blend cold air with the heated air. If it's stuck closed the AMM can get fried.
go to this website and download
Volvo Problem Solver Advanced Edition-1.pdf
http://www.volvowiringdiagrams.com/?dir=volvo/Trouble%20Shooting%20Guides
then go to the Home page and find the Green Books for your year.
PS Download everything you cid think you will need and I'm amazed that this site is still running after many years.
OH - Merry Christmas
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Thanks, CB. I pulled up that manual and I'm going to work my way through it. No green books for the 87 on there though. Only for the 1975. I'm on my second MAF/AMM. It seemed to help but the screw adjustment doesn't seem to help. Both AMMs test fine on the meter.
Oh, the box thermostat - I changed that out a few weeks ago and installed a new lone from the exhaust manifold (the one that looks like a tiny dryer hose). But before that you're right, that thermostat had failed. Next time it fails I'll just delete, because I don't live in the tundra. But, I'm still not sure that helps with the diagnosis since replacing the hose to the throttle body had fixed the idle problem before I took it apart and put it back together.
Merry Christmas to you too!
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posted by
someone claiming to be CB
on
Mon Dec 25 15:36 CST 2017 [ RELATED]
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re Volvo Wiring Diagrams website.
The Green Books are not labeled as such. From the Home Page - every sub system IS the Green Book for that System. Or they were once upon a time.
Seems like most of the folders have lost the .pdfs....
A shame. several years ago I downloaded every pdf on the site.
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Thanks again, CB. I have pulled everything I can from that site, which seems to be some 90s computer drawings of the wiring schematics for various systems. The troubleshooting guide looks great and now I have that too.
I think there used to be complete copies of the green books online as downloadable pdfs but they were taken down a few years ago and the volvotips site got some kind of exclusive license. They, unfortunately, have opted to display them as flash files, making them nearly unusable. Not only is the page excruciatingly slow to operate, it's also only usable online. I'm not going to bring my laptop out to the garage while working on the jalopy and put the same greasy fingerprints on it that I get all over the paper manuals, which still work after you get them filthy. If you poke into the html you can download the flash object but I have so far been unable to figure out how to convert them to pdfs. It's really unfortunate that this is the only way they are available for free online now. I hardly think Volvo can be profiting from this, and we're losing because of it.
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